Electric switch



April 15 1924. 1,490,432

J. T. RHAMSTINE ELECTRIC SWITCH Filed Feb. 5, 1920 gwuenk o J. 111m mane.

Patented Apr. 15, 1924.

UNITED STATES I 1,490,432 PATENT oFFicE.

JOHN THOMAS RHAMSTINE, OF DETROIT, MICHIGAN.

ELECTRIC SWITCH.

Application filed February 5, 1920. Serial No. 356,520.

To all whom it may concem:

Be it known-that I, JOHN THOMAS RHAM- STINE, a citizen of the United States, residing at Detroit, in the county of Wayne and State of Michigan, have invented a new and useful Improvement in Electric Switches, of

which the following is a specification.

The present invention relates to electric switches, and particularly to those of the.

type controlled by timing mechanism.

An object is to provide a time controlled switch which may be easil set; which is of relatively small compact-fi irm; which comprises relatively few movable parts; which is designed to maintain a circuit closed for .a desired period of time; and which positively breaks the circuit and maintains the same open upon the termination of the time.

period for which the switch may be set.

Another object of the invention is to provide a time controlled switch which ma be cheaply and easily manufactured; w ich may be made rapidly and in large numbers;

and which may be installed as a part ofv 1 being illustrated in the accompanying drawing, wherein;

Fig. 1 is a side elevation partly in section of a time controlled switch constructed according to the present invention.

Fig. 2 is a face view thereof.

Fig. 3 is a detail underside erspective view of the contact disc of the evice, and

Fig. 4 is a detail perspective view of the pivoted contact arm and its mounting.

Referring to the drawing by numerals, 10 designates a casingwhich maybe cylindrical in form and of any desired depth, the same having a bottom 11 and a rotatable top or cap 12.

A plate or partition 13 is arranged in the casing in spacedrelation to the bottom 11 and divides the casing into upper and lower compartments. A suitable turning mechanism 14, of preferably the spring actuated type as shown, is mounted in the lower compartment of the casing 10 and is supported upon a plate or false bottom 15 secured in the casing near the bottom 11. This turning mechanism has an arbor'or shaft 16 which rises through the partition 13 and extends upwardly through the cap 12. The cap 12 turns with and may be detachably mounted on the arbor 16 by a nut l7,'or the like, admitting removal of the cap 12 and access to the casing for cleansing, adjustment of the parts, and the like.

Fixed upon th 'arbor 16 in the upper compartment is a disc 18' forming one con tact in a circuit from wire 19 through the timing mechanism 14 and the arbor 16. The contact disc 18 carries on its under side a circuit breaking or insulating block 20 arranged near the outeredge of the disc and having beveled or cam ends for a purpose which will hereinafter appear.

The timing mechanism 14 urges the arbor 16 to turn in one direction, such as in an anti-clockwise direction, and the disc 18 carries a movable stop 2]. adapted to engage a fixed stop 22 carried by the casing 10 and 'nto the path of the movable projectin 1 stop .21. lhe' stop 22 may be in the form of a screw passing through a reinforced side of the casing 10 and which detachably holds a fixed.pointer 23 on the upper end of the casing. The pointer overhangs the edge of the cap 12, and the latter has a dial 24 divided into consecutively numbered time intervals, such as minutes, beginning and ending at a zero point 25. The movable stop 21 is so positioned on the contact disc 18 as to 25 registers with the pointer 23.

The partition 13 carries an u standing bracket arm 26 seated upon an insulating strip 27 and connected to the other wire '28 of the circuit. The wire 28 may pass up through the bottom 11, plate 15 and partition 13, and is insulated therefrom by a covering 29 of rubber or the like. The wire 19 ma be secured directly to the casing near t e bottom as shown, or the current may be conducted to the contact disc in any other suitable manner.

Pivoted at one end on the bracket arm 26 is a movable contact arm 30 adapted to extend toward the contact disc 18 and urged therea ainst by a spring 31 which is seated on a b ock 32 secured to the partition 13. The block 32 has a spring seating inclined to support the sprin 31 an stantially at right angles to an beneath the pivoted contact arm 80. The free end of face 90 engage the fixed stop 22 when the zero point p the arm 30 is curved downward to form a shoe or sliding surface adapted to bear against the lower side of the contact disc 18.

The timing mechanism 14 normally holds the stops 21 and 22 in engagement with each other and the zero point 25 in register with the pointer 23. In this normal position of rest, the insulating block 20 lies between the disc 18 and the arm 30 to break and hold open the circuit.

To operate, the edge of the cap 12, which may be milled or roughened as shown, is grasped between the fin ers and turned clockwise until the desire time indication on the dial 24 re isters with the pointer 23. This turning of t e cap 12 in a clockwise direction also winds the spring of the timing mechanism 14 to ut it into condition for subsequent operation. The turning of the cap 12 by hand also rotates the disc contact 18 and moves the insulating blocln 20 from between the disc 18 and the contact finger 30, which latter is urged against the disc 18 by the spring 31 and completes the circuit.

Current now flows throu h the circuit, and as soon as the cap 12 is ie eased from; the hand the timing mechanism turns the arbor 16 and the parts carried thereby anti-clockwise until the stops 21 and 22. come together, during all which time the circuit is closed. As the stops 21 and 22 come together the disc 18 brings the block 20 against the pivoted arm 30 and moves the latter away from the disc; thus breaking the circuit as the parts come to rest. Of course the timing mechanism, is retarded in its 0 oration proportionately to the character 0 the eriod of time divisions on the dial 2 1, so t at should the cap 12 be set at 5 it would take a eriod of time equal to five times the perio of time designated between the graduations for the cap 12 to return to rest and break the circuit.

he switch, therefore, normally maintains the circuit open, and can be optionally ad- 'iiusted to keep the circuit closed various engths of time for different uses and conditions met with in the use of the switch.

above specifically described embodiment of this invention Without departing from the spirit thereof, the changes and modifications being restricted only by the scope of the following claims.

What is claimed is 1. An electric switch comprising a casing, a clock mechanism mounted in the bottom of the casing and having main arbor disposed coaxially in the casing, a cap for the casing fixed to the arbor for movement by the clock mechanism and for rewindin the same, a contact disc mounted on the ar or in the upper part of the casing adapted to turn with the arbor, a stationary contact mounted in the upper part of the casing and normally urged against the contact disc for completing a circuit therethrough, and an insulating member carried by the disc to travel there with and arranged in the path of the stationary contact for spacing the same from the disc when the latter is in its normal position of rest.

2. In an electric switch, a casing, an arbor coaxial in the casing, a clock mechanism connected to the arbor for urging the same to turn in one direction, a cap for the casing fixed upon the arbor adapted to turn therewith in one direction for operation of the switch and adapted to be turned in the opposite direction for rewindin the clock mechanism, a disc mounted on the arbor in the upper part of the casing, a stationary contact in t 1e casing normally urged toward the disc for closing a circuit therethrou h, cooperating stops on the disc and easing or determining a position of rest of the disc and clock mechanism, an indicator carried by the casing and arranged to coact with the cap for indicating the extent of rewinding of the clock mechanism and the turning of the disc out of its normal position of rest,

and an insulating block carried by the disc in position to en age the stationary contact spaced the same rom the disc when the latter is in its position of rest.

h In1 witness whereof I hereunto set my JOHN THOMAS RHAMSTINE. 

